Conversion of hydrocarbon oils



Jan. 12, 1937. E. F. NELSON I CONVERSION OF HYDROCARBON OILS original Filed Nov. 1o, 1930 mmZ ZOU INVENTOR EDWIN F. NELSONv Patented Jan. 12, 1937 UNITED STATES PATENT OFFICE CONVERSION OF HYDROCARBON OILS Application November 10, 1930, Serial No. 494,550 Renewed February 12, 1935 3 Claims.

This invention relates to the conversion of hydrocarbon materials and particularly refers to the simultaneous conversion of hydrocarbon oil and natural gas.

5 The present invention embodies the concepts of an improved process and apparatus wherein natural gas or other hydrocarbon gas of similar nature is subjected to conversion at an elevated temperature, preferably under super-atmospheric pressure, and the products of such conversion are utilized to assist the conversion of relatively heavy hydrocarbon oil into lighter and more valuable products.

In amore specific embodiment of the invention a hydrocarbon gas, such as natural gas or any hydrocarbon material of a similar nature in a gaseous state, is subjected to elevated temperatures in a heating element, preferably maintained under super-atmospheric pressure, to eiect 2 conversion of the gas preferably into substantial quantities of aromatic compounds and hydrogen,

the eiuent from the heating element being rich in aromatics and hydrogen. Simultaneously hydrocarbon oil is subjected to conversion condi- 2 tions in a separate heating element, the materials resulting from conversion of the gas being introduced into the stream of hydrocarbon oil entering said separate heating element or into the stream of heated materials emerging from 30 said separate heating element or partially into both streams; the combined heated materials are introduced into an enlarged' reaction zone where separation of vapors and unvaporized residual material is effected, vapors from said enlarged reaction zone being subjected to fractionation, the relatively heavy insufficiently converted portion of the vapors being condensed in the fractionating zone and returned to reconversion, and the relatively light portion of the fraction- 40 ated vapors of the desired composition being subjected to condensation and cooling and the products collected.'

'I'he attached diagrammatic drawing illustrates one form of apparatus in which the process of the, present invention may be practiced and the following description of the drawing embraces also a description of the operation of the process as it may be practiced in the` apparatus shown.

Raw oil charging stock for the process introduced through line I and valve 2 to pump 3 may be fed through line 4 and valve 5 into fractionator 6 where it is preheated by contact with vapors in this zone assisting in their fractionation and passing together with the heavier condensed portion of the vapors through line l and valve 8 to pump 9. A portion or all of the raw oil charging stock may, if desired, be diverted from line 4 and from fractionator 6 and is fed through line II) controlled by valve Il into line 'l where it combines with the reflux condensate from 5 fractionator 6, passing to pump 9. The combined materials are fed by pump 9 through line I2 and valve I3 into heating element I4.

Heating element I4 is located in any suitable form of furnace I5 and the materials passing 10 therethrough are heated to the desired conversion temperature under any desired pressure conditions and pass therefrom through line I6 and valve I `I into reaction chamber I8.

Hydrocarbon gas, such as natural gas or any 15 other hydrocarbon material of similar nature in a gaseous state, is supplied through line I9 and valve to pump 2I, is fed through line 22 and Valve 23 into heating element 24, which is located in any suitable form of furnace 25 and in which 20 the gas is heated to the desired conversion temperature under any desired pressure conditions. Materials leaving heating element 24 may pass through line 26 and valve 2l or through line 52, valve 53, pump 54, Valve 55 and line 56 and 25 may be passed through line 28 and valve 29 into line I2 combining therein with the stream of oil passing to heating element I4. Likewise a portion or all of the materials from heating element 24 may pass from line 21 or line 56, as 30 the case may be, through line 30 and valve 3| into line I6 combining therein with the stream of heated materials from heating element I4. A portion of the material discharged from heating element 24 may be recirculated thereto for re- 35 conversion by diverting it from line 28 through line 32 controlled by valve 33 and through line I9 to pump 2l.

The combined materials from heating elements I4 and 24 pass through line I6 and valve II to 40 reaction chamber I8 where separation of vapors and unvaporized material is permitted. Unvaporized residual liquid may be withdrawn from chamber I8 through line 34 controlled by valve 35 to storage or to further treatment as desired. 45

Vapors from chamber I8 pass through line 36 and Valve 31 to fractionator 6 where they are subjected to fractionation, their relatively heavy insufficiently converted portion being condensed therein and returning to reconversion, as already described, while the relatively light fractionated vapors of the desired composition pass through line 38 and valve 39, are subjected to condensation and cooling in condenser 4I),v condensed and uncondensed products from which a blend of approximately 60 percent benzol and pass through line 4I and valve 42 to be collected in receiver 43. Condensed distillate may be Withdrawn from receiver 43 through line 44 and valve 45. Uncondensed gaseous products may be y released through line 46 controlled by valve 41.

A portion of the condensed distillate from receiver 43,may be withdrawn through line 48 and valve 49 and recirculated by means of pump 50 through line 5I and valve 51 to fractionator 6 to assist fractionation of the vapors in this zone.

Substantially equalized pressure may be employed throughout the system or dierential pressures may be utilized between the various elements. Conversion temperatures employed may range from 750 to 1600 F., more or less. Preferably the gas is subjected to more severe conversion conditions than those employed in the heating element utilized for the conversion of the oil.

As a specific example of operating conditions which may be employed in an apparatus such as illustrated andthe improved results which may be obtained from such operation, the raw oil charging stock is a fuel oil of about 22. A.'P. I.

gravity and is subjected in heating element I4, together with approximately 6 percent by weight, based'on the raw oil charging stock, of material. from heating element 24, to a conversion temperature of approximately 880 F. under a super-atmospheric pressure of about 350 pounds per square inch. About 20 percent by weight of natural gas, based upon the raw oil charging stock, is subjected in heating element 24 to a conversion temperature of approximately 1200 F. under a super-atmospheric pressure of 7about 1500 pounds per square inch.

Products 'from the conversion of the gasv introduced, in part, to the inlet of heating element I4, as already described, and in part tothe outlet from `heating element I4 pass together with the converted oil from heating element I4 to reaction chamber I8 wherein a pressure of about 350 pounds persquare inch in maintained. Thispressure is substantially equalized in the succeedingportions of thel system, namely, the fractionating, condensing and Ycollectingl equipment. A yield of about 65 percent of motor fuel having anti-knock characteristics equivalent to 40 percent straight-run Pennsylvania -gasoline may be obtained. In addition about 20fpercent of residual oil substantially free from suspended carbonaceous material and suitable for sale as premium fuel and about 10 percent.' ofpressure distillate bottoms suitable as cracking stock for ,ducing gaseous hydrocarbons may be obtained. The above yields are based on the Volume ofl raw oil charged to the system. The uncondensable gas produced by the system is approximately equivalent to the natural gas fed to the system butis higher in calorifc value and richer in' hydrogen content vthan the natural gas and may be utilized in hydrogenating processes, may be blended with gas of lower caloric value to improve its quality, or may be otherwise utilized as desired. f

1. A process for converting hydrocarbon oils comprising'passing charging oil into a primary y heating zone wherein it is subjected to cracking conditions of temperature and pressure, introinto a second heating zone and subjecting them to temperature and pressure conditions adequate to produce aromatic hydrocarbons and hydrogen, withdrawing the conversion 4products from the second heating zone and commingling at least a portion thereof with the charging oil entering the primary heating zone, another portion of the conversion products being recycled to the second heating z one. A

2. A` process for converting hydrocarbon oils comprisingv passing charging oil into a primary heating zone rwherein it is subjected to cracking conditions of temperature and pressure, intro- A ducing gaseous hydrocarbons linto a second heating zone and subjecting them to temperature and pressure conditions adequate t'o produce aromatic hydrocarbons 'and hydrogen, withdrawing the conversion products from the second heating zone and commingling at least a portion thereof with'the hot oil leaving the pri-' mary heating zone, anotherportion of the conversion products being recycled through the secondheating zone.`

*3g-A' process for converting hydrocarbon oils comprising passing charging oil linto a primary heating zone in' which it is subjected to cracking conditions of temperature and pressure, introducing gaseous 'hydrocarbons into a second heating zone andy subjecting them to 'temperature =andpre'ssure conditions adequate to producev aromatic hydrocarbons land hydrogen, withdrawing the conversion products from the second heating zone, commingling oneA portion thereof with the'charging oil entering the primary heating zone and commingling another portion 'thereof with thev hot oil leaving the primary heating zone, la further portion beingk recycled through the second heating zone. 

